Cobalt-containing monoazo dyestuffs



United States Patent O COBALT-CONTAINING MONOA ZO DYESTUFFS GuidoSchetty, Basel, Switzerland, assignor to J. R. Geigy A. G., Basel,Switzerland, a Swiss firm No Drawing. Application January 2, 1953,Serial No. 329,459

Claims priority, application Switzerland January 5, 1952 7 Claims. (Cl.260-147) Water soluble, chrome-containing monoazo dyestuffs aredescribed in U. S. Patent No. 2,551,056 and in the applicants copendingpatent application Serial No. 298,827, filed July 14, 1952, which arederived from those o.o-dihydroxydyestuffs which contain no acid groupsrendering them water soluble but which, on the other hand aresubstituted by at least one'low molecular alkylsulphonyl group havingatmost carbon atoms. It is due to .this alkylsulphonyl group that thesecomplex chrome compounds are suitable for the fast and level dyeing ofwool and similar synthetic fibres from an aqueous neutral to Weakly aciddyebath.

On further work being done on the subject of the invention, it has nowbeen found that these o.o-dihydroxy monoazo dyestuffs which have no acidwater-solubilising groups of the general formula:

A represents the radical of an o-hydroxydiazo component,

B represents the radical of an azo component coupling in .a neighbouringposition to a phenolic or enolic hydroxyl group, and

Rrepresents a low molecular aliphatic hydrocarbon radical.

The alkyl sulphonyl groups are aromatically bound and the radicals A andB may contain non-ionogenic substit- .uents. In particular, thesecomplex cobalt compounds differ from the comparable complex chromecompounds in that they generally have a new shade, generally stronglyshifted towards the hypsochrome and they are distinguished by an evenbetter fastness to light.

' The monoazo dyestuffs usable according to this invention arecharacterised by the absence of acid watersolubilising groups such ascarboxyl and sulphonic acid groups and by the presence of at least onearomatically bound low molecular alkyl-sulphonyl group which may beeither in the diazo or in the coupling component. It is the presence ofthis particular alkylsulphonyl group which makes the complex cobaltcompounds according to this invention sufiiciently water soluble. Thediazo and. coupling components containing alkylsulphonyl groups can beused for the production of suitable 0.0- dihydroxy monoazo dyestufis, e.g. 4-methylsulphonyl-, 4-ethylsulphonyl, 4-nor i.-propylsulphonyl-,4-n.-butylsulphonyland 4-'amylsulphonyl-2-amino-l-phenols andacetoacetylaminobenzene-alkyl sulphones,l-alkylphenylsulphonyl-3-methyl-5-pyrazolones, 1-hydroxy-3- or -5-alkylsulphonyland 2-hydroxy-6-alkylsulphonyl-naphthalenes andderivatives thereof substituted in the aromatic rings by non-ionogenicsubstituents such as halogen, methyl, nitro-, acylamino groups, etc.Naturally, also all those diazo and coupling components which have noacid water-solubilising groups but which, however, may be substituted bynon-ionogenic substituents, previously used for the production ofo.o'-dihydroxy dyestuifs can be used in the combinations with at leastone alkylsulphonyl group as defined according to this invention.o-Aminophenols, o-aminonaphthols, acetoacetanilides, pyrazolones,2.4-dihydroxyquinolines, phenols, naphthols, etc. come intoconsideration.

The monoazo dyestuffs usable according to this invention are metallis'edby treating them with agents giving off cobalt, e. g. with solublecobalt salts of inorganic or, advantageously, organic acids such ascobalt chloride, cobalt sulphate or cobalt acetate. Metallisation isperformed, for example, in aqueous solution or suspension at a raisedtemperature, and if desired, in the presence of inert organic solventssuch as low alcohols and of mineral acid neutralisers or acid bindingagents such as alkali acetates or carbonates at either normal orincreased pressure. The agent giving off cobalt should be used in suchamounts that there is at least 1 cobalt atom to every two molecules ofdyestutf. To ensure that the end products are sufficiently watersoluble, they can be mixed with sufiicient amounts of alkali carbonateor phosphate and, if desired, with capillary active dispersing agents.

As well as for the fast and level dyeing from a weakly acid to neutraldyebath of wool and synthetic fibres similar thereto composed ofsuperpolyamides, superpolyurethanes and casein, the new dyestuifs arealso suitable for the dyeing of silk and leather. The dyeings producedwith the cobalt-containing dyestuffs according to this invention haveexcellent fastness to light.

The following examples illustrate the invention without limiting it inany way. Where not otherwise stated, parts are given as parts by weightand the temperatures are in degrees centigrade. The relationship ofparts by weight to parts by volume is as that of kilogrammes to litres.

Example 1 O B 3-0 Ha -N=N cn dolom (BO-MFG 18.7 parts ofZ-amino-l-hydroXybenzene-4-methyl sulphone are dissolved in 17 parts ofconcentrated hydrochloric acid and 150 parts of water and diazotised at5 with 6.9 parts of sodium nitrite. The diazo suspension is neutralisedwith sodium bicarbonate and then 3 parts of sodium bicarbonate areadded. A solution of 18.6 parts of acetic acid anilide in 250 parts ofWater and 11.4 parts by volume of 10 N-caustic soda lye is added, thewhole is heated at 65 for 30' minutes and the dyestuff is precipitatedby the addition of 20 parts by volume of 10 N-hydrochloric acid. It isfiltered otf, washed until the washing water is neutral and then stirredinto 500 parts of water. 60 parts of cobalt acetate (corresponding to3.54 parts of Co) and 5.5 parts of anhydrous soda are then added and thewhole is heated for 15 hours at -90". 700 parts of a 25% sodium chloridesolution are added and after cooling, the complex compound whichprecipitates is filtered off. After drying, a yellow brown powder isobtained which dyes wool very evenly from a weakly acid bath in dullyellow shades.

u. to.

18.7 parts of 2-amino-l-hydroxybenzene-4-methyl, sulphone are dissolvedin 150 parts of water and 17 parts of concentrated hydrochloric acid anddiazotised at 5 with an aqueous concentrated solution of 6.9 parts ofsodiumnitrite. The diazo compound precipitates in the form of,clay-yellow coloured small crystals. The suspension is made neutraltolitmus paper by the addition of sodium hydrogen carbonate, then 3 partsof sodium hydrogen carbonate are added and a solution of 21.9 parts ofl-(3-chlorophenyl)-3-methyl-5-pyrazolone and 6 parts of sodium hydroxidein 200 parts of water are added. The whole is stirred without coolinguntil the formation of the dyestuff is complete, which, is for about 5hours, whereupon it is heated to 85 and the dyestufi, which precipitatesalmost quantitatively in crystal form, is filtered oft hot. While stilldamp, the dyestutf is heated in 500 parts of water with 60 parts ofcobalt acetate solution (corresponding to 3.54 parts of Co) for 1 hourat 80 after which 11 parts of anhydrous soda are added until there is analkaline reaction to phenolphthalein and the whole is then stirred for 5hours at 8085. 1000 parts of a sodium chloride solution are added, thecobalt complex compound which precipitates is filtered off and dried. Abrown powder is obtained which dissolves well in hot water and dyes woolfrom a neutral or weakly acid dyebath in orange yellow shades. Thedyeings are distinguished by very good fastness to washing, milling andsea water and by excellent fastness to light.

It, instead of 18.7 parts of Z-amino-l-hydroxybenzene- 4-methylsulphone, 20.1 parts of 2-amino-1-hydroxybenzene-4-ethyl sulphone or21.5 parts of Z-amino-l-hydroxybenzene-4-n.-propyl sulphone are used,dyestuffs are obtained which have a somewhat better drawing power from aneutral bath.

23.2 parts of S-nitro-Z-amino-1-hydroxybenzene-4- methyl sulphone aredissolved in 100 parts of water and 10 parts by volume of 10 N-causticsoda lye, a 33% sodium nitrite solution is added (corresponding to 6.9parts of sodium nitrite) and the whole is poured within 1 hour at 48into a solution of 28 parts of concentrated hydrochloric acid and 50parts of water. The diazonium compound so obtained is coupled asdescribed in Example 2 with 21.9 parts of 1-(3-chlorophenyl)-3-methyl-S-pyrazolone. The dyestuif obtained is heated for 16 hours at7580 in 500 parts of water with 60 parts of cobalt acetate solution(corresponding to. 3.54 parts of Co) and the cobalt complex compoundwhich precipitates is filtered oil and, after drying, is mixed with 30%of its weight of trisodium phosphate. The new cobalt-containing dyestutfdyes wool from a neutral or 4. weakly acid bath in orange shades whichhave very good fastness to milling, sea water and light.

Example 4 OH OH 22.2 parts of 6-chloro-2-amino-1-hydroxybenzene-4-methyl sulphone are dissolved in 200 parts of hot water with 18 parts ofconcentrated hydrochloric acid, the solution is cooled to 5 anddiazotised with 6.9 parts of sodium, nitrite in 20 parts of water. Oncompletion of the diazotisation, the suspension is neutralised withsodium hydrogen carbonate and then poured at 05 into a solution preparedfrom 15.1 parts of 2-hydroxynaphthalene, 400 parts of water, 10.5 partsby volume of 10 N-caustic sodalye and 15 parts of anhydrous soda. Oncompletion of the formation of the dyestuff, it is filtered off, pastedin 500 parts of water at and 60 parts of a cobalt acetate solution(corresponding to 3.54 parts. of Co) are added. The whole is stirred at80 and 1.7 parts of hydrogen peroxide in the form of a 3% solution areadded dropwise within 1 hour. Stirring is continued for a further 5hours at 80 whereupon the liquid is made alkaline to soda, and thecobalt-containing dyestuif is precipitated with common salt and filteredoff. After drying, it is in the form of a dark brown powder which dyeswool from a neutral or weakly acid bath in wine red shades which haveexcellent fastness to light. The dyeings are distinguished by very goodfastness to washing, milling, alkali and sea water.

If, instead of 22.2 parts of 6-chloro-2-amino-l-hydroxybenzene-4-methylsulphone, 18.7 parts of 2-amino-l-hydroxybenzene-4-methyl sulphone areused, a dyestuff is obtained which does not draw quite so well from aneutral bath but dyes in somewhat more pure shades.

The following table givessome further examples which can be obtained bythe process described in detail above.

Shade of the cobalt compound on wool Diazo component Coupling component2-amino-1-hydroxybenzene-i-methyl sulphone.

carbomcthoxyaminoviolet.

naphthol-(L7).

2-naphthol-G-mothyl sulp one. 6-bromo-2-naphthol. wine red.

5.8-dichloro-1-naphthoL red violet. Z-naphthol l red.

. .do do 6-nitro-2-amino-1-hydrox-ybenz'ene-tmethyl sulphone.4-nitto-2-aminophenol )row nish violet.

1-(4methylsulphonylphenyl) -3-mcthyl-5- nyrazolone.

Z-hydroxynaphthalinfi-mcthyl sulphono.

2-hydroxynaph thalene wine red.

brownish rc red.

3-acetylamino-4-mcthy!- l-phcnol 5. Dyeing example 2 parts of thedyestufi obtained according to Example 4 are dissolved in 3000 parts ofwater, 10 parts of Glaubers salt and 2 parts of ammonium sulphate areadded. parts of wool are entered at 50, the bath is brought to the boilwithin half an hour and is kept at the boil for 1 /2 hours while movingthe goods well. The goods are then rinsed and'dried. The wool which hasbeen dyed a wine redshade is very fast to washing, alkali, sea water andlight.

5 What I claim is: 1. The complex cobalt compound of a monoazo dyestuffhaving the formula:

H CH1 [halal M,

wherein B represents the radical of a member selected from the groupconsisting of phenolic, naphtholic, S-pyrazolonic andacetoacetyl-anilidic coupling components containing the OH-group ino-position to the azo group and is otherwise free from carboxylic acidand sulphonic acid groups.

3. The complex cobalt compound of a monoazo dyestutf having the formula:

4. The complex cobalt compound of a monoazo dyestufi having the formula:

01 on on sown,

5. The complex cobalt compound of a monoazo dyestuff having the formula:

SOQCHI 6. The complex cobalt compound of a monoazo dyestuff having theformula:

lMm O CHs 7. The complex cobalt compound of a monoazo dyestufi havingthe formula:

OH OH References Cited in the file of this patent UNITED STATES PATENTSCarson June 15, 1948 Schetty May 1, 1951 OTHER REFERENCES Crossley:Metallized Azo Dyes, American Dyestutf Reporter, March 7, 1938, pages124-125.

1. THE COMPLEX COBALT COMPOUND OF A MONOAZO DYESTUFF HAVING THE FORMULA: